Corrugated metallic foil tape

ABSTRACT

A metallic foil tape having a top surface and a bottom surface with an adhesive applied to at least one of the top surface or the bottom surface of the metallic foil tape and corrugations in the metallic foil tape providing for expansion of the corrugated metallic foil tape in a circular or semi-circular shape. The corrugated metallic foil tape is suitable to be applied to contoured or three-dimensional surfaces, and is particularly suitable for use in sealing or joining components of heat, ventilation, and air conditioning (HVAC) units.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of and claims priority from U.S. patentapplication Ser. No. 12/290,842, filed on Nov. 4, 2008. The disclosuresof which are incorporated herein by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates to a corrugated metallic foil tape, moreparticularly to a corrugated metallic foil tape for use in heating,ventilation, and air conditioning units, or related applications.

BACKGROUND OF THE INVENTION

It is of growing global concern not only to conserve energy but also tomitigate loss of energy. One such example is with loss of energy inresidential or commercial buildings.

There are many known approaches in use today to attempt to address thisproblem of mitigating energy loss. It is known to use sealants, ductmastic and caulking for sealing around the joints of a heating,ventilation and air conditioner (HVAC) unit. Common sealants includebutyl, polyurethane and acrylic sealants. In the case of a sealant, thesealant is typically applied by painting the joint or crack around theheating, ventilation, and air conditioning unit, particularly aroundjoints or seams at the plenum, trunk registers or other duct branches.The sealant is subsequently cured after being applied. Among thedisadvantages with such sealants and mastics, for example, are that theyare often cumbersome and messy to apply and, once applied, are typicallynot readily removable or adjustable.

There are also known disadvantages associated with duct tape. It isoften advised not to use duct tape in HVAC applications. According tothe International Energy Conservation Code published by theInternational Code Council in IECC 2003 803.2.8 for Duct and PlenumInsulation and Sealing: “All joints, longitudinal and transverse seams,and connections in ductwork, shall be securely fastened and sealed withwelds, gaskets, mastics (adhesives), mastic-plus-embedded fabricsystems, or tapes. Tapes and mastics used to seal ductwork shall belisted and labeled in accordance with UL 181A or UL 181B. Ductconnections to flanges of air distribution equipment shall be sealed andmechanically fastened . . . duct tape is not permitted as a sealant onany metal ducts.” For example, over time conventional duct tape cracksand results in leaks in the system. This creates problems as the jointsor seams in a HVAC unit are often inaccessible after installation.

There are also known disadvantages associated with flat HVAC ratedaluminum tapes. Such flat aluminum tapes when applied around a circularvent or air duct, for example, leave gaps through which energy canescape. These tapes are often time consuming to apply to minimize gapsaround contoured surfaces. Furthermore, they are not easily pliablearound such surfaces and readily tear.

Since most duct leakage occurs at the connection to registers, plenumsor branches in the duct system, at each of these connections a method ofsealing the duct system is required. Field examination of duct systemshave typically shown that these seals tend to fail over extended periodsof time. ASTM Test Method E 2342-03, which is the standard test methodfor “Durability Testing of Duct Sealants,” evaluates the durability ofduct sealants by blowing heated air into test sections, combined with apressure difference between the test sections and their surroundings. Inthe Method E 2342-03, the temperatures and pressures were chosen toexpose the test sections to typical conditions that are found inresidential duct systems. The duct leakage site geometry represents aleakage site commonly found in duct systems. Therefore, there is a needfor a more efficient and reliable method to seal joints, and hencemitigate energy loss, in a HVAC unit, particularly in the plenum, trunkregisters or other duct branches of a HVAC unit.

SUMMARY OF THE INVENTION

The present invention relates to a metallic foil tape having a topsurface and a bottom surface with an adhesive applied to at least one ofthe top surface or the bottom surface of the metallic foil tape andcorrugations in the metallic foil tape providing for expansion of thecorrugated metallic foil tape in a circular or semi-circular shape. Thecorrugated metallic foil tape is suitable to be applied to contoured orthree-dimensional surfaces, and is particularly suitable for use insealing or joining components of heat, ventilation, and air conditioning(HVAC) units.

The present invention also relates to a method of making the corrugatedmetallic foil tape and a method of using the same.

The corrugated metallic foil tape of the present invention solves theproblems associated with energy loss in HVAC units and provides anefficient, clean, and resilient alternative to known tapes and sealantsused in such applications.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples, whileindicating the preferred embodiment of the invention, are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is an illustrative drawing of a corrugated metallic foil adhesivetape in accordance with the present invention.

FIG. 2A illustrates corrugations in a corrugated metallic foil adhesivetape in accordance with the present invention.

FIG. 2B illustrates the profile of the corrugated metallic foil adhesivetape of FIG. 2A.

FIG. 3 illustrates corrugations at other than a ninety degree angle in acorrugated metallic foil adhesive tape in accordance with the presentinvention.

FIG. 4A is an illustrative drawing of another corrugated metallic foiladhesive tape in accordance with the present invention.

FIG. 4B illustrates the profile of the corrugated metallic foil adhesivetape of FIG. 4A.

FIG. 5 is an illustration of a single continuous piece of corrugatedmetallic foil tape in accordance with the present invention applied in acircular or semi-circular shape to the vent of an air duct.

FIG. 6 is a photograph of a corrugated metallic foil tape in accordancewith the present invention configured in a form of a semi-circle.

FIG. 7 is a photograph of a conventional foil tape configured in a formof an arc of a circle.

FIG. 8 is a photograph of a single continuous piece of corrugatedmetallic foil tape in accordance with the present invention applied in acircular or semi-circular shape to the vent of an air duct.

FIG. 9 is a photograph of pieces of conventional foil tape applied in acircular or semi-circular shape around the vent of an air duct.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description of the embodiment(s) is merelyexemplary in nature and is in no way intended to limit the invention,its application, or uses.

The tape of the present invention is a corrugated metallic tape forsealing joint or seams in a heating, ventilation and air conditioner(HVAC) unit. The joint or seam is typically associated with the plenum,trunk register or other duct branches in the HVAC unit. The tape of thepresent invention is particularly suited for sealing the HVAC collar tothe plenum or to other parts of the HVAC unit where there are contoured,angled, or three-dimensional surfaces to which the tape needs to beapplied. A plenum typically refers to a sealed chamber at the inlet oroutlet of an air unit to which ductwork is attached.

The metallic foil tape of the present invention is corrugated to havecorrugations. The terms “corrugated” and “corrugations,” as used herein,refer to regular indentations or markings including, but not limited to,folds, grooves, ridges, or furrows. Referring now to the figures, FIG. 1illustrates a corrugated metallic foil tape 100 in accordance with thepresent invention. As illustrated in FIG. 2A, it is preferred that thecorrugations are parallel to one another. FIG. 2B illustrates theprofile of the corrugated metallic tape of FIG. 2A. The corrugations maybe at a 90 degree angle as measured from the lengthwise edge(s) 20 ofthe corrugated metallic foil tape 200 as shown in FIG. 2A.Alternatively, the corrugations may be at an angle other than a 90degree angle as measured from the lengthwise edge(s) 30 of thecorrugated metallic foil tape 300 as shown in FIG. 3. FIG. 2A alsoillustrates the widthwise edge(s) 22 of the corrugated metallic foiltape 200 and FIG. 3 also illustrates the widthwise edge(s) 32 of thecorrugated metallic foil tape 300.

As illustrated in FIGS. 2B and 4B, the corrugations in the tape may beof different shapes, sizes, and pitches. An advantage of the corrugatedmetallic foil tape of the present invention is that due to beingcorrugated, the tape is easier to stretch and conform without tearing,hence making the tape more durable, which is an improvement over theconventional flat metallic tapes that are being used in the industry.Commercially available flat metallic foil tapes may be obtained andsubsequently corrugated in accordance with the method of the presentinvention. Examples of flat metallic foil tapes that are suitable foruse in accordance with the present invention include, but are notlimited to, Ideal IS 2000, Ideal 587A, Ideal 490, Nashua 324, Polyken339, Fasson 0810, Fasson 0800, Venture 1581A, Compac 340, 3M-Scotch3326, Shurtape AF 100, Venture 1581A, Ideal Seal 2000, IdealSeal-587A/B, Fasson 0810, Covalence, Nashua 324A.

The metallic foil tape typically has a thickness in the range of fromabout ½ mil to about 5 mil, preferably about 2 mil in thickness. Anexample of a metallic foil tape suitable for use in the presentinvention is an aluminum foil tape.

Prior to being corrugated, a flat metallic foil tape may be directlycoated with an adhesive then laminated to a release liner or indirectlycoated with an adhesive by laminating the foil to a release liner withadhesive on it. The adhesive is generally applied to the flat metallicfoil tape before corrugation. As discussed above herein, the corrugatedmetallic foil tape comprises a top surface and a bottom surface. Eitherthe top surface or the bottom surface of the corrugated metallic foiltape comprises an adhesive coating.

Preferably, the adhesive is a high shear adhesive or an adhesive havingholding power. For example, an adhesive that has good holding powerwould have the ability to withstand greater shear stress (i.e. forcesapplied parallel or tangential to a face of a material). ASTM D 3654 isa standard test method for Holding Power of Pressure Sensitive Tapes. Ahigh shear adhesive is preferred over a low shear adhesive in HVAC unitapplications because a high shear adhesive works at low temperature andhigh temperature conditions. Typically, a tape with a low shear adhesivehas a tendency to tear or split under such conditions.

Preferably, the high shear adhesive is a pressure sensitive adhesive(PSA). The term “pressure sensitive adhesive,” as used herein refers to,a material which in dry form is generally aggressively and permanentlytacky at room temperature and firmly adheres to a variety of dissimilarsurfaces upon mere contact without the need of more than typicallyfinger or hand pressure. A pressure sensitive adhesive typically doesnot require activation by solvents or heat and adheres firmly to a widevariety of surfaces.

The pressure sensitive adhesive may be solvent based, water based, or in100% solid form. Suitable types of pressure sensitive adhesives include,but are not limited to, acrylic, butyl rubber, natural rubber,polyurethane, styrene-butadiene rubber (SBR), synthetic isoprene rubber,ethylene vinyl acetate copolymers, and silicones.

The adhesive is applied to form a coating having a thickness of about0.1 mil to about 5 mil, preferably about 1.5 to 2.5 mils. The adhesivecoating is applied by any means known to one of ordinary skill in theart including, but not limited to, reverse roll, knife over roll, andextrusion coating onto a release liner which can be based on paper,clay, coated paper, glassine, film or any other material known in theart, then laminated to foil.

Referring to the figures, FIGS. 2B and 4B illustrate a corrugatedmetallic foil tape in accordance with the present invention havingdifferent cross-sectional views. FIG. 2B, for example, illustrates thatthe corrugated metallic foil tape has a top surface 24 and a bottomsurface 26. As shown in FIG. 2A, the corrugated metallic foil tape 200also has opposing edges both lengthwise 20 and widthwise 22. Each ofthese figures illustrate the corrugations in the tape may be ofdifferent shapes, sizes, and pitches.

The present invention also provides a method of making a corrugatedmetallic foil tape. The method comprises obtaining a flat metallic foiltape, and corrugating the flat metallic foil tape. The metallic tape iscorrugated either manually or automatically to make regular indentationsor markings in the tape. For example, one such method of corrugating thetape is a press with roller bars through which the uncorrugated tape isrun, wherein the roller bars have demarcations or raised portions on thesurfaces of the roller bars such that when the tape is fed between theroller bars, corrugations are made in the metallic tape. Manual orautomated means can be used to run the tape through the rollers.Alternatively, presses or other mechanical devices or equipment may beused to apply pressure to the tape as it is corrugated.

As discussed previously herein, there has been a growing need to solvethe problems associated with energy loss, particularly in HVAC units.Among the numerous advantages associated with the corrugated metallicfoil tape of the present invention is that it is able to conform to andagainst curved and three-dimensional surfaces without tearing andwithout destroying the integrity of the tape. FIG. 5 illustrates thecorrugated metallic foil tape 500 of the present invention applied in acircular or semi-circular shape to an HVAC unit. The corrugated metallicfoil tape of the present invention offers improved performance overconventional foil tapes as shown below in the examples where,particularly in these HVAC applications, a more durable, easilyremovable, and more efficient alternative is desired.

In the present invention, the tape is particularly suitable to beapplied in a circular shape or into semi-circular segments or shapes. Byhaving been corrugated, the metallic foil tape is easier to stretch andconform to a contoured, angled, or three-dimensional surface. By beingcorrugated, the metallic foil tape can be extended outward to form asmaller inside diameter and a larger outside diameter. There can bedifferent angles and different shapes to the corrugations. The pitch canalso be adjusted.

For example, as shown in FIG. 5, the corrugated metallic foil tape 500of the present invention mates with the exterior dimensions of thecollar flange of the plenum. The corrugated metallic foil tape 500expands and stretches such that it conforms and is flush to thecontoured, angled, or three-dimensional surface of the HVAC unit.

EXAMPLE Metal Tapes

FIG. 6 is a photograph of a corrugated metallic foil tape in accordancewith the present invention configured in a form of a semi-circularsegment or shape.

For comparative purposes, FIG. 7 is a photograph of a conventional foiltape configured in a form of an arc of a circle. It can be seen fromFIG. 7 that the foil tape tears when trying to conform it in the shapeof a circle.

FIG. 8 is a photograph of a single continuous piece of corrugatedmetallic foil tape in accordance with the present invention appliedaround the circular vent of an air duct. The corrugated foil tape shownin FIG. 8 was applied in one continuous piece and had an installationtime of two minutes and nine seconds.

For comparative purposes, FIG. 9 is a photograph of pieces ofconventional foil tape applied around the circular vent of an air duct.The installation time for the standard foil tape shown in FIG. 9required five pieces of tape, Shurtape AF 100, and had an installationtime of three minutes and 54 seconds.

EXAMPLE Duct Tape

An experiment was conducted for the following tapes in accordance withASTM E2342 and the results of the experiment are set forth in Table 1.

TABLE 1 Time to Failure in Days Tape (Tested to the requirements of(Minimum 60 days ASTM E2342) required by the test) Duct Tape [CovalenceNashua 557, 1-13 Covalence Nashua 558 CA, Shurtape PC 857, and ShurtapePC 858 CA] Duct tape backing with acrylic adhesive 1-35 Corrugated foiltape with acrylic adhesive 69+ in accordance with the present invention(using Shurtape AF 100 aluminum foil tape prior to corrugation)

It will therefore be readily understood by those persons skilled in theart that the present invention is suitable for broad utility andapplication. Many embodiments and adaptations of the present inventionother than those herein described, as well as many variations,modifications and equivalent arrangements, will be apparent from orreasonably suggested by the present invention and the foregoingdescription thereof, without departing from the substance or scope ofthe present invention. Accordingly, while the present invention has beendescribed herein in detail in relation to its preferred embodiment, itis to be understood that this disclosure is only illustrative andexemplary of the present invention and is made merely for purposes ofproviding a full and enabling disclosure of the invention. The foregoingdisclosure is not intended or to be construed to limit the presentinvention or otherwise to exclude any such other embodiments,adaptations, variations, modifications and equivalent arrangements.

What is claimed is:
 1. A method of making a metallic foil tape, themethod comprising: obtaining a flat metallic aluminum foil tape having atop surface and a bottom surface, obtaining a release liner having apressure sensitive adhesive applied directly thereon, applying therelease liner to the flat metallic aluminum foil tape wherein thepressure sensitive adhesive is between the flat metallic aluminum foiltape and the release liner, feeding the flat metallic aluminum foil tapewith the release liner to a corrugator, and corrugating the flatmetallic aluminum foil tape with the release liner to form corrugationsin the flat metallic aluminum foil tape and the release liner.
 2. Themethod according to claim 1, wherein the corrugations in the corrugatedmetallic foil tape provide for expansion of the corrugated metallic foiltape in a circular or semi-circular shape.
 3. The method according toclaim 1, wherein the pressure sensitive adhesive is selected from thegroup consisting of acrylic, synthetic rubber, natural rubber,polyurethane, styrene-butadiene rubber (SBR), synthetic isoprene rubber,ethylene vinyl acetate copolymers, and silicone.
 4. The method accordingto claim 1, wherein the corrugations are parallel to one another.
 5. Amethod of making a metallic foil tape having a top surface and a bottomsurface, the method comprising: obtaining a flat metallic foil tape,obtaining a release liner having a pressure sensitive adhesive applieddirectly thereon, applying the release liner to the flat metallic foiltape wherein the pressure sensitive adhesive is between the flatmetallic foil tape and the release liner, feeding the flat metallic foiltape with the release liner to a corrugator, and corrugating the flatmetallic foil tape with the release liner to form corrugations in theflat metallic foil tape and the release liner, wherein the corrugationsare parallel to one another.
 6. The method according to claim 5, whereinthe corrugations in the corrugated metallic foil tape provide forexpansion of the corrugated metallic foil tape in a circular orsemi-circular shape.
 7. The method according to claim 5, wherein thepressure sensitive adhesive is selected from the group consisting ofacrylic, synthetic rubber, natural rubber, polyurethane,styrene-butadiene rubber (SBR), synthetic isoprene rubber, ethylenevinyl acetate copolymers, and silicone.
 8. The method according to claim5, wherein the flat metallic foil tape is an aluminum foil tape.
 9. Amethod of making a metallic foil tape, the method comprising: obtaininga flat metallic aluminum foil tape having a top surface and a bottomsurface, applying a pressure sensitive adhesive to at least one of thetop surface or the bottom surface of the flat metallic aluminum foiltape using a release liner having the pressure sensitive adhesiveapplied directly thereon, and corrugating the flat metallic aluminumfoil tape with the release liner to form corrugations in the flatmetallic aluminum foil tape and the release liner.
 10. The methodaccording to claim 9, wherein the corrugations in the corrugatedmetallic foil tape provide for expansion of the corrugated metallic foiltape in a circular or semicircular shape.
 11. The method according toclaim 9, wherein the pressure sensitive adhesive is selected from thegroup consisting of acrylic, synthetic rubber, natural rubber,polyurethane, styrene-butadiene rubber (SBR), synthetic isoprene rubber,ethylene vinyl acetate copolymers, and silicone.
 12. The methodaccording to claim 9, wherein the corrugations are parallel to oneanother.
 13. The method according to claim 9, wherein the release lineris applied to the flat metallic aluminum foil tape by lamination priorto corrugation.
 14. A method of making a metallic foil tape, the methodcomprising: obtaining a flat metallic aluminum foil tape having a topsurface and a bottom surface, laminating a release liner having apressure sensitive adhesive applied directly thereon to at least one ofthe top surface or the bottom surface of the flat metallic aluminum foiltape, and corrugating the flat metallic aluminum foil tape with therelease liner to form corrugations in the flat metallic aluminum foiltape with the release liner.
 15. The method according to claim 14,wherein the corrugations in the corrugated metallic foil tape providefor expansion of the corrugated metallic foil tape in a circular orsemicircular shape.
 16. The method according to claim 14, wherein thepressure sensitive adhesive is selected from the group consisting ofacrylic, synthetic rubber, natural rubber, polyurethane,styrene-butadiene rubber (SBR), synthetic isoprene rubber, ethylenevinyl acetate copolymers, and silicone.
 17. The method according toclaim 14, wherein the corrugations are parallel to one another.
 18. Amethod of making a metallic foil tape, the method comprising: obtaininga flat metallic foil tape having a top surface and a bottom surface,applying a pressure sensitive adhesive to at least one of the topsurface or the bottom surface of the flat metallic foil tape using arelease liner having the pressure sensitive adhesive applied directlythereon, and corrugating the flat metallic foil tape with the releaseliner to form corrugations in the flat metallic aluminum foil tape andthe release liner.
 19. A method of making a metallic foil tape, themethod comprising: obtaining a flat metallic foil tape having a topsurface and a bottom surface, laminating a release liner having apressure sensitive adhesive applied directly thereon to at least one ofthe top surface or the bottom surface of the flat metallic foil tape,and corrugating the flat metallic foil tape with the release liner toform corrugations in the flat metallic foil tape and the release liner.